Design for unnecessary capacity or capacity should be considered a design flaw. This includes engineering "one size fits all" solutions

Unnecessary Capacity

In a perfect world, a manufacturing facility has to be built to meet the demand. Since the customer demand depends on various factors such as competition, economy, customer preference, etc., it is very hard to predict the actual demand. Therefore, the marketing division provides either a range of value for the demand or provides a maximum planning volume and most likely volume to the manufacturing division to build the facility.

From sustainability point of view, building the manufacturing site to mostly like volume is preferred. If the demand is higher than the most likely volume, then one cam manage the demand by adding over time or additional shift. If the demand is lower than the most likely volume, then consider product innovation actions (late point differentiators’) to increase the demand to achieve the most likely volume.

Unnecessary Capability

Similar to building unnecessary capacity, designing with unnecessary capability will consume additional resources during all stages of the life cycle. For example, if the vehicle is designed to operate at all times in Alaska’ December temperature, then the design will be inefficient and not optimal to operate in normal operating temperatures.

One Size Fits All

The major pro of one size fits all designs is the cost-efficiency: higher production rate, lower startup costs (since fewer parts/machines are needed), and cost reduction through learning and bulk purchase of materials or constituent parts. The downside to one size fits all is that such products tend to be overdesigned for any particular user's purposes, since they must satisfy the diverse needs of all users.

Customized designs solve these problems by designing to what is needed and no more. Thus, the custom design will result in a less complex system and minimizes the material required to produce a product. By minimizing the waste, customization is more sustainability-friendly. However, customization requires additional R&D time and funding, more investment in the manufacturing machinery for the different parts, and results in a lower production rate, all of which might result in higher cost and price for the product.